An assessment of electrolytic hydrogen production from H2S in Black Sea waters

In the deeper parts of the Black Sea basin, water is anoxic. Hydrogen sulfide (H2S) occurs naturally, and its concentration is nearly constant, around 9.5 mg/L at 1500 m depth. Its high solubility, and the existing chemical environment facilitate its accumulation and containment in the seawater, and its extraction poses a challenge.Possibility of hydrogen and sulfur production from H2S contained in the waters of Black Sea is investigated conceptually. A multistage process is considered which involves extraction of seawater, adsorption of H2S, electrochemical production of hydrogen and polysulfides; fresh water production by desalination of seawater and further hydrogen production from the resulting salty solution through chlorine–alkaline electrolysis. Some consideration is included regarding the economic and environmental aspects of the process.

► Remediation of natural and industrial waters from H2S via hydrogen production. ► Anoxicity and H2S in Black Sea. ► Conceptual process for H2 production from H2S in Black Sea. ► Recovery of H2S by activated carbon and H2 production by its electrolysis. ► Estimation of process efficiency, energy consumption, and product cost.